Process for the synthesis of organic condensation products.



HAROLD HIBBERT, 0F WILMINGTON, DELAWARE, ASSIGNOB TO E. I. DU POINT DE NEMOURS POWDER COMPANY, OF WILMINGTON, DELAWARE, A CORPORATION OF NEW JERSEY.

PROCESS FOR THE SYNTHESIS OF ORGANIC GONDENSATION PRODUCTS.

No Drawing.

To all whom it may concern:

Be it known that I, HAROLD HIBBERT, of

Wilmington, in the county of New Castle and in the State of Delaware, have invented a certain new and useful Improvement in Processes for the Synthesis of Organic Condensation Products, and do hereby declare that the following is a full, clear, and exact description thereof.

My invention relates particularly to the production of condensation products from organic compounds, but it has reference more particularly to the production of condensation products from aldehydes, ketones, etc., and the synthesis of aldols by such condensation.

It has been well known that organic compounds such as aldehydes, ketones, etc., in the presence of alkali or alkaline salts, undergo condensation. For instance, the aldehyde or aldehydes in the presence of an alkaline solution undergoes the condensation known as the aldol condensation; that is to say, two molecules of the aldehyde unite to form an aldehyde alcohol or aldol derivative. In the case of acetaldehyde forming acetaldol, the change would be as follows:

0H,.OHO CH,.CHO- CH,.CHOH.CH,CHO

A disadvantage of the condensations as previously carried out is that such condensations have been eifected in general in an aqueous or alcoholic solution. The process when carried out in this manner is expensive, owing to the cost involved in isolating the pure product. A further disadvantage has been in the formation of resinous products, especially where aqueous solutions have been employed, thus resulting in poor yields.

In a recent application of mine, Serial No. 696,342, filed May 10, 1912, I have sought to overcome this difiiculty by the action of a solid condensing medium on a mixture of the aldehyde with an inert solvent such, for example, as gasolene, which latter is miscible with the aldehyde but immiscible with the condensation product. When a condensing agent such as caustic soda is used in such a mixture, with acetaldehyde, acetaldol is formed which is insoluble in gasolene and of a higher specific ravity, so that it at once separates out, co lecting at the bottom of the vessel so as to be thus readily capable of isolation from the remaining compounds present.

Specification of Letters Patent.

amalgam containing about 1% Patented Apr. 9, 1918.

Application filed November 28, 1913. Serial No. 803,438.

I have discovered that such condensations and especially those carried out in connection with aldehydes, may be effected by the presence of a small quantity of an alkali metal or an alkaline earth metal, either in the isolated state or in the form of a mixture, alloy or amalgam. By the term metal I thus mean to include the metal whether in the isolated state or in the form of a mixture, alloy or amalgam. In producing the condensation in this manner, no solvent is required, although a solvent may be used, if desired, without interfering with the course of the reaction. Furthermore, I have found that in some instances an alcohol or similar liquid forming an alkaline salt, may be added when found desirable, although this is not necessary.

My invention may be carried out in many difierent ways but for the purpose of illustration I may proceed as -follows: 200 grams of freshly distilled and preferably practically anhydrous acetaldehyde are cooled preferably to about -6 C. with a freezing mixture, and then about 0.15 grams of finely divided sodium are added. The contents are then preferably shaken ever few minutes for about an hour, keeping t e temperature preferably below 5 C., and then for another sixteen or eighteen hours at preferably 0 C. During the process, the sodium completely disappears. After neutralization, by the addition of a saturated solution of sodium bisulfate, for example, and distilling off the unchanged acetaldehyde, a very pure acetaldol remains behind.

While in the above example I employ 0.15 grams of sodium, I do not wish to limit myself to this amount since much larger quantities may be employed. Thebest results are obtained, by using not more than 0.5% of sodium, calculated on the weight of acetaldehyde taken. I

I have found that the sodium may be substituted by an amalgam of sodium or any other alkali or alkaline earth metal, so as to obtain equally satisfactory results. An example of this may be the following: 100 grams of freshly distilled and practically anhydrous acetaldehyde are cooled to preferably 9 C. and 16 grams of a sodium are added. These materials are kept in a freezing mixture and are preferably well shaken from time to time in order to preof sodium terials is permitted to rise-to preferably 8 C. and is kept at this temperature with an occasional shaking for a period of prefer ably sixteen hours. After neutralization by the addition of a saturated solution of sodium bisulfate and distilling off the un-.

changed acetaldehyde, a very good yield of very pure acetaldol remains.

tAs previously indicated, the reaction may be varied, if desired, by the addition of a little alcohol. This may be added prior to the addition of the condensing agent. An example of the process as carried out in this manner may be as follows: 100 grams of acetaldehyde are mixed with 6 cc. of practically anhydrous ethyl alcohol and the mixture-cooled toabout 8 C. 16 grams of a sodium amalgam containing about 1% sodium are then introduced, the materials being kept preferably in a freezing mixture and shaken in order to avoid any undue rise of temperature. After'abo'ut one hour, the materials are transferred from the freezing mixture to ice water so as to maintain the temperature around approximately 0 C. for

about sixteen hours. After neutralization by the addition of an aqueous sodium bisulfate solution,"the excess of acetaldehyde is removed by distillation, thereby leaving behind as a residue very pure acetaldol. I

have found that in the above exa ple instead of alcohol any other liquid capable of forming an alkaline salt may be employed. Furthermore, it is to be understood that if desired the procedure may be varied by carrying out the condensation in a cooled mixture of practically anhydrousaldehyde with some inert solvent miscible with the aldehyde but immiscible with the condensation with an alkali-forming metal.

2. .The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to the action of an alkali metal in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali metal.

3. The process of condensation which comprises subjecting an organic compound con-- taining a carbon atomand an oxygen atom united by a double bond of union, to the action of sodium in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

. 4. The process of condensation which'comprises subjecting an aldehyde to the action of an alkali-forming metal in the presence of a substantially anhydrous liquid organic compound capableof forming a salt with an alkali-forming metal.

'5. The process of condensation which comprises subjecting an aldehyde to the action of an alkali metal in the'presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali metal. I

6. The process of condensation which comprises subjecting an aldehyde to the action of sodium in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

7. The process of condensation which comprises subjecting acetaldehyde to the action of an alkali-forming metal in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali-forming metal."

8. The process of condensation which comprises subjecting acetaldehyde to the action of 'an alkali metal in the presence of a substantially anhydrous liquid organic compound capable of forming a salt'with an alkali metal.

9. The process of condensation which comprises subjecting acetaldehyde to the action of sodium in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

10. The process of condensation which comprises subjecting an organic compound containing-a carbon atom and an oxygen atom united by a double bond of union, to the action of an a1kali-forming metal, in a mixture of the organic compound with a solvent which is misciblewith the organic compound but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with analkaliforming metal.

11. The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to

the action of an alkali metal, in a mixture of the organic compound with a solvent which is miscible with the organic compound but immiscible with the condensation products in the presence of a substantially anhydrous liquid organic compound capable of fqrming a salt with an alkal -forming meta 12. The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to the action of the sodium, in a mixture of the organic compound with a solvent which is miscible with the organic compound but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

13. The process of condensation which comprises subjecting an aldehyde to the action of an alkali-forming metal, in a mixture of the aldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali-forming metal.

14. The process of condensation which comprises subjecting an aldehyde to the action of an alkali metal, in a mixture of the aldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali-forming metal.

15. The process of condensation which comprises subjecting an aldehyde to the action of sodium, in a mixture of the aldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product intne presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

16. The process of condensation which comprises subjecting acetaldehyde to the action of an alkali-forming metal, in a mixture of the acetaldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali-forming metal.

17. The process of condensation which comprises subjecting acetaldehyde to the action of an alkali metal in a mixture of the acetaldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with an alkali-forming metal.

18. The process of condensation which comprises subjecting acetaldehyde to the action of sodium, in a mixture of the acetaldehyde with a solvent which is miscible with the aldehyde but immiscible with the condensation product in the presence of a substantially anhydrous liquid organic compound capable of forming a salt with sodium.

19. The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to the action of an alkali-forming metal, and then neutralizing and distilling ed the unchanged organic compound.

20. The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to the action of an alkali metal, and then neutralizing and distilling oil the unchanged organic compound.

21. The process of condensation which comprises subjecting an organic compound containing a carbon atom and an oxygen atom united by a double bond of union, to the action of sodium, and then neutralizing and distilling ofi' the unchanged organic compound.

22. The process of condensation which comprises subjecting an aldehyde to the action of an alkali-forming metal, and then neutralizing and distilling ofi the unchanged aldehyde.

23. The process of condensation which comprises subjecting an aldehyde to the action of an alkali metal, and then neutralizing and distilling off the unchanged aldehyde.

24. The process of condensation which comprises subjecting an aldehyde to the ac tlon of sodium, and then neutralizing and distilling oil the unchanged aldehyde.

25. The process of condensation which comprises subjecting acetaldehyde to the act1on of an alkali-forming metal, and then neutralizing and distilling ofi the unchanged acetaldehyde.

26. The process of condensation which comprises subjecting acetaldehyde to the action of an alkali metal, and then neutralizilngl and distilling off the unchanged acetaldeiy e.

27. The process of condensation which comprises subjecting acetaldehyde to the action of sodium, and then neutralizing and distilling off the unchanged acetaldehyde.

In testimony that I claim the foregoing T have hereunto set my hand.

HARQLD HTBBERT.

Witnesses:

HAMILTON BRADSHAW, Roxanna: J. LILLEY. 

